Pediatrics Flashcards

Question

Teeth in pediatric patients

Answer 1

**Primary**: 7 months to 2 or 3 years **Permanent**: 6 years to 20 years

Answer 2

birth except not all the nerves are myelinated * Rapid for 2 years * Complete by 7 years

Answer 3

few months

Answer 4

* Posterior fontanelle closed by 4 months * Anterior fontanelle closed by 18 months - 2 years

Answer 5

metabolism of brown fat (nonshivering thermogenesis)

Answer 6

larger surface area per kilogram, thin skin and low-fat content

Answer 7

inadequately warmed operating room environment, administration of room temperature intravenous fluid and dehumidified anesthetic gases

Answer 8

delayed awakening from anesthesia, cardiac arrhythmias and respiratory depression

Answer 9

using warm blankets/bair hugger, covering the patient’s head; and warming the OR, mattress and IV fluids

Answer 10

* Pediatric patients have a larger **ECF compartment and greater TBW** (total body water) * **Larger loading dose of water-soluble drugs are required** due to dilutional effect lowering plasma drug concentration * **Higher plasma concentrations for lipid-soluble drugs occur due to decreased fat and muscle volume**

Answer 11

TBW: 85% ECF: 60% ICF: 25%

Answer 12

TBW: 80% ECF: 45% ICF: 35%

Answer 13

TBW: 60% ECF: 25% ICF: 35%

Answer 14

TBW: 60% ECF: 20% ICF: 40%

Answer 15

**Total plasma protein levels are lower in infants** (reach adult concentrations by 5-6 months of age) •Protein binding of many anesthetic drugs are lower in young children

Answer 16

_Organ development_ •Immature organ systems, metabolic degradation pathways, and blood brain barrier _Organ blood flow_ •Greater blood flow to vessel-rich organs

Answer 17

* heart murmur * cyanosis * hypertension * exercise intolerance

Answer 18

* asthma/reactive airway disease (RAD) * recent upper respiratory infection (\<4 weeks prior to surgery)

Answer 19

* anemia * bruising, abnormal bleeding, coagulopathy * sickle cell anemia

Answer 20

* neuromuscular disease including hypotonia * congenital abnormalities including genetic syndromes * Medications * Family history of adverse reactions to anesthesia * Malignant hyperthermia * prolonged paralysis or need for ventilation after anesthesia * Allergies

Answer 21

_Hematologic testing_ CBC and coagulation studies should be performed in patients with a **suspected, known, or a family history of bleeding disorders**, prior to surgery that is likely to result in significant bleeding, such as **tonsillectomy/adenoidectomy, cleft palate repair, and intracranial procedures** _Electrolytes_ Electrolytes should be performed in children with **renal insufficiency, endocrine disorders, and those with history of vomiting/diarrhea**

Answer 22

0.5 to 1.2 percent

Answer 23

ASA 1 or 2 **Significant OSA** (especially those \< 3 years old) are at significant risk for airway obstruction and desaturation after adenotonsillectomy; these patients should have inpatient monitoring after surgery **Ex-premature infants** (born before 37 weeks gestation) are at risk for apnea after anesthesia or sedation. This risk decreases with increasing postmenstrual age (PMA) (ie, gestational age plus chronological age) with minimal risk between 56 and 60 weeks postconception. Ex-premature infants may require recovery room level of care overnight after anesthesia. **Neonates** - Most institutions require inpatient observation after anesthesia for infants ≤44 weeks PMA, since full term infants may be at risk for apnea after anesthesia in the first few weeks of life

Answer 24

a sedative, such as midazolam (0.3–0.5 mg/kg, **15 mg maximum**). Of note, the **onset of oral midazolam is 20 – 45 minutes**.

Answer 25

Intramuscular midazolam or Ketamine with atropine may be helpful.

Answer 26

* **Alarm limits should be appropriately adjusted** * A precordial or esophageal stethoscope and smaller ECG pads and BP cuff (potentially placed on the lower extremity) may be used * **Temperature must be closely monitored** because of greater risk for malignant hyperthermia and greater susceptibility for intraoperative hypothermia or hyperthermia * **Air bubbles should be removed from pressure tubing** and small volume flushes should be used to avoid air embolism, unintended heparinization, or fluid overload * **Glucose measurement** may be warranted in premature or small-for-gestational-age neonates * Monitors **may sometimes need to be first attached following induction** of anesthesia in less cooperative patients

Answer 27

**Intravenous**: The advantages of an intravenous technique include availability of intravenous access if emergency drugs need to be administered and rapidity of induction in the child at risk for aspiration. **Inhalational** * Many children do not arrive in the operating room with an intravenous line in place * **The child breaths an odorless mixture of nitrous oxide (70%) and oxygen (30%). Sevoflurane (or halothane) can be added to the gas mixture in 0.5% increments every few breaths.** * An intravenous line can be started after an adequate depth of anesthesia has been achieved.

Answer 28

**Intramuscular succinylcholine** (4 mg/kg, not to exceed 150 mg) and **atropine** (0.02 mg/kg, not to exceed 0.4 mg) should be available if laryngospasm or bradycardia occurs before an intravenous line is established.

Answer 29

Nitrous oxide is a **relatively odorless gas** that is generally very well tolerated in healthy children, as either a primary agent or adjunct to the delivery of halogenated compounds. Nitrous oxide may be administered to achieve unconsciousness, but is **not potent enough to allow airway manipulation when used as a sole agent**. Nitrous oxide speeds the induction of high solubility gases like halothane but adds little to the speed of induction of less soluble gases such as sevoflurane. Introduction of nitrous oxide is odorless and if the patient accepts the mask, several minutes of nitrous oxide may decrease the aversive response to the introduction of the more malodorous sevoflurane. **Often an inhalational induction will include either high concentrations of nitrous oxide and oxygen (limited to 70 percent N2O and 30 percent O2 to prevent hypoxemia), or a combination of N2O, O2, and sevoflurane.**

Answer 30

**Sevoflurane is the most commonly used agent for inhalation**. **It is relatively insoluble, which provides a rapid onset.** It is less pungent, and less irritating to the airway than desflurane and isoflurane, and is associated with less airway related problems (ie, laryngospasm and bronchospasm) during induction and emergence.

Answer 31

Infants are usually upset by having a mask placed over their face, regardless of the odor of the gas. The mask is gradually applied while administering sevoflurane 5% with or without 70% nitrous oxide in oxygen. Sevoflurane is increased to 8% as tolerated.

Answer 32

Toddlers are induced similarly to infants, although nitrous oxide alone with oxygen may be used for the first several breaths prior to introducing sevoflurane to achieve some level of "stunning" prior to the "smelly gas". Some institutions apply a pleasant smelling ointment (usually fruit flavor lip balm) to the inner surface of the face mask to obscure the odor of the anesthetic gas.

Answer 33

Older children can often be engaged by telling them the mask is like an astronaut's mask and that they are like an astronaut blasting into space, breathing oxygen to protect them. Similar to toddlers, a pleasant smelling lip balm is added to the mask, and sevoflurane is administered with or after nitrous oxide in oxygen, depending on their degree of cooperation.

Answer 34

Teenagers may be induced in a manner similar to school age children. Alternatively, if cooperative, they may be able to perform a single breath induction. For a single breath induction, the breathing circuit is primed with 8% sevoflurane and 70% N2O. The patient expires completely, the mask is placed tightly over his or her face, and the patient then inspires fully and holds his or her breath. This achieves rapid loss of consciousness, but is often followed by return to Stage II anesthesia.

Answer 35

the concentration of sevoflurane should be reduced to minimum alveolar concentration (MAC) level, closer to 3 percent. **The signs of reaching Stage III include a slower, regular rate of respiration, decreased heart rate, and cessation of muscle movements. Eyes are midline, not divergent.** Although it is possible to achieve a depth of anesthesia sufficient for endotracheal intubation with sevoflurane alone, it can take several minutes for this to occur. Most commonly depth of anesthesia is increased by the administration of **propofol 2 to 3 mg/kg** after the intravenous catheter is placed. Alternatively, muscle relaxant can be given, if indicated by the procedure.

Answer 36

Sevoflurane: 3.2 Isoflurane: 1.6 Desflurane: 8-9

Answer 37

Sevoflurane: 3.2 Isoflurane: 1.8-1.9 Desflurane: 9-10

Answer 38

Sevoflurane: 2.5 Isoflurane: 1.3-1.6 Desflurane: 7-8

Answer 39

* The saphenous vein has a consistent location at the ankle * Twenty four-gauge catheters are adequate in neonates and infants when blood transfusions are not anticipated * All air bubbles should be removed from the intravenous line

Answer 40

* The infant’s prominent occiput tends to place the head in a flexed position prior to intubation. This is easily corrected by slightly elevating the shoulders on towels and placing the head on a doughnut-shaped pillow. * **Straight laryngoscope blades** can be helpful for intubation of the anterior larynx in neonates, infants, and young children

Answer 41

* The appropriate **diameter** inside the endotracheal tube can be estimated by a formula based on age: **4 + (Age/4) = Tube diameter (in mm)** * Endotracheal tubes 0.5 mm larger and smaller than predicted should be readily available in or on the anesthetic cart * **Estimate of endotracheal length: 12 + (Age/2) = Length of tube (in cm)** * The CRNA can intentionally advance the tip of the endotracheal tube into the right mainstem bronchus and then withdraw it until breath sounds are equal over both lung fields

Answer 42

* Pressure control ventilation- set peak inspiratory pressures of 15 to 18 cm H2O should be used for neonates, infants, and toddlers to prevent barotrauma. * Volume control ventilation (6 to 8 mL/kg) may be used for larger pediatric patients

Answer 43

* Small tidal volumes can also be manually delivered with greater ease with a 1-L breathing bag rather than with a 3-L adult bag. * Pediatric breathing circuits are usually shorter, lighter, and stiffer

Answer 44

Can be determined by the “4:2:1 rule” 4 mL/kg/h for the first 10 kg of weight, 2 mL/kg/h for the second 10 kg, and 1 mL/kg/h for each remaining kilogram. (practice some examples of this for the exam)

Answer 45

* In addition to a maintenance infusion, any preoperative fluid deficits must be replaced * Preoperative fluid deficits are often administered with hourly maintenance requirements in aliquots of 50% in the first hour and 25% in the second and third hours

Answer 46

premature neonates (100 mL/kg) full-term neonates (85–90 mL/kg) infants (80 mL/kg) adults (65–75 mL/kg)

Answer 47

•An initial hematocrit of 55% in the healthy full-term neonate gradually falls to as low as 30% in the 3-month-old infant before rising to 35% by 6 months. Hemoglobin (Hb) type is also changing during this period: from a 75% concentration of HbF (greater oxygen affinity, reduced PaO2, poor tissue unloading) at birth to almost 100% HbA (reduced oxygen affinity, high PaO2, good tissue unloading) by 6 months

Answer 48

3: 1 - crystalloid: blood loss 1: 1 colloid: blood loss •Blood loss has been typically replaced with non–glucose-containing crystalloid (eg, 3 mL of lactated Ringer’s injection for each milliliter of blood lost) or colloid solutions (eg, 1 mL of 5% albumin for each milliliter of blood lost) until the patient’s hematocrit reaches a predetermined lower limit.

Answer 49

•In recent years there has been increased emphasis on **avoiding excessive fluid administration**; thus blood loss is now commonly replaced by either **colloid** (eg, albumin) or **packed red blood cells.**

Answer 50

In premature and sick neonates, the target hematocrit (for transfusion) may be as great as 40% healthy older children a hematocrit of 20% to 26% is generally well tolerated.

Answer 51

•Because of their small intravascular volume, neonates and infants are at an increased risk for electrolyte disturbances (eg, hyperglycemia, hyperkalemia, and hypocalcemia) that can accompany rapid blood transfusion.

Answer 52

Platelets and fresh frozen plasma, 10 to 15 mL/kg, should be given when blood loss **exceeds** **one to two blood volumes.** Recent practice, particularly with blood loss from trauma, favors “earlier” administration of plasma and platelets as part of a massive transfusion protocol.

Answer 53

One unit of platelets per 10 kg weight raises the platelet count by about 50,000/μL. The pediatric dose of cryoprecipitate is 1 unit/10 kg weight.

Answer 54

**ABL = EBV (Hi - Hf) divided by Hi** Hi = initial hct Hf = final lowest accceptable

Answer 55

**relatively atraumatic surgery = 0 to 2 mL/kg/hr** (eg, strabismus correction where there should be no third-space loss) **traumatic procedures = 6 to 10 mL/kg/hr** (eg, abdominal abscess)

Answer 56

Lactacted Ringers

Answer 57

* Administration of an opioid: **Fentanyl, 1–1.5 mcg/kg** * **Dexmedetomidine: 0.5 mcg/kg,** (given slowly with heart rate monitoring) **15 to 20 min before the end of the procedure** can reduce the incidence of emergence delirium and agitation if the surgical procedure is likely to produce postoperative pain

Answer 58

•The choice between awake and deep extubation is based on patient factors and clinician preference. - **Awake extubation** allows the return of airway tone and airway protective reflexes, and theoretically reduces the risk of post-extubation airway obstruction and laryngospasm. - **Deep extubation** may be preferred children with risk factors for bronchospasm, or in whom coughing should be avoided for surgical reasons.

Answer 59

* Aspiration (eg, ileus, upper gastrointestinal bleeding) * Airway obstruction (eg, after cleft palate repair, craniofacial anomalies, obstructive sleep apnea) * Airway muscle weakness associated with neuromuscular or cranial nerve disorders

Answer 60

less coughing * Patients at high risk of bronchospasm (eg, asthma, recurrent wheezing) * After thyroidectomy, due to risk of hematoma at surgical site, and airway compromise * After tracheal surgery, to avoid disruption of the suture line

Answer 61

* Prior to awake extubation, the neuromuscular blocking agent (if used) should be completely reversed * the oropharynx should be suctioned * the patient's eyes should be conjugate (rather than deviated) as a sign of recovery from anesthesia * patient should respond by grimacing or opening eyes in response to stimulation or suctioning

Answer 62

•Prior to deep extubation, the patient should be 1. **breathing spontaneously** 2. regular respirations 3. adequate tidal volumes

Answer 63

by lack of coughing or change in ventilatory pattern with the following maneuvers: 1. Move the endotracheal tube in the trachea to mimic the stimulation of extubation 2. Thoroughly suction the oropharynx. Retained oropharyngeal secretions may precipitate laryngospasm during emergence after deep extubation 3. Empty the stomach with an orogastric tube.

Answer 64

• a patent **mask airway** should be established and maintained during emergence and transport to the post-anesthesia care unit (PACU). We transport patients to the PACU in the **lateral decubitus position**, slightly head down, to maintain airway patency and allow secretions to drain.

Answer 65

•Some instutions remove most supraglottic airways (SGAs) while the patient is still deeply anesthetized. **Awake** removal of an SGA allows **return of airway tone** and **protective reflexes** while a patent airway is maintained. However, an *SGA does not protect against aspiration or laryngospasm during emergence*, and the patient may cough, bite on the LMA tube, gag, or vomit during emergence. If the patient bites on the tube while emerging, it may be impossible to remove the device, or to ventilate. •The decision to remove an SGA deep or awake should be based on patient factors and clinician preference, and data to support either choice is inconclusive

Answer 66

Awake removal of an SGA is similar to awake extubation. The oropharynx should be suctioned on either side of the SGA.

Answer 67

Prior to deep removal of an SGA, the patient should be **breathing spontaneously with regular respirations** and **adequate tidal volume**. If the patient has been maintained on pressure support, the mode of ventilation should be changed to **spontaneous**.

Answer 68

1. Maintain expired anesthetic gas concentration at ≥1 MAC 2. Suction the oropharynx on both sides of the SGA, and verify no change in ventilatory pattern or movement in response to suction 3. After removal of the SGA, an oral airway should be placed, ventilation should be maintained by mask, and the anesthetic agent should be discontinued.

Answer 69

The patient should be transferred to the PACU stretcher or bed with care taken to **avoid neck flexion**, which could **cause stimulation of the larynx** by the oral airway with positioning to ensure continued airway patency.

Answer 70

*Laryngospasm is more common during emergence from anesthesia than during induction.* •**Prevention** – Strategies for prevention of laryngospasm on emergence include the following: 1. **Suction** the oropharynx thoroughly to remove secretions, either while the patient is still deeply anesthetized, or awake, but **not** during light anesthesia. 2. Avoid extubation or airway manipulation during a light level of anesthesia. 3. Administer **lidocaine** via laryngotracheal atomizer at and below the vocal cords immediately prior to intubation, or lidocaine 1 to 1.5 mg/kg IV two to five minutes prior to extubation 4. Administer a **positive pressure breath** while extubating awake, to force secretions away from the vocal cords, and to abduct vocal cords.

Answer 71

*Treatment of laryngospasm during emergence depends on the severity of the episode.* 1. Initial treatment includes administration of 100 percent oxygen by face mask, with gentle positive pressure ventilation 2. A small dose of propofol (0.25 to 0.8 mg/kg IV) may reverse laryngospasm in this setting.

Answer 72

For severe laryngospasm unresponsive to these maneuvers: * succinylcholine should be administered * succinylcholine 0.25 to 0.5 mg/kg IV * Bradycardia -→ Atropine 0.02 mg/kg IV * Once laryngospasm breaks, the airway must be supported with mask ventilation, and if necessary, intubation.

Answer 73

•If laryngospasm is recognized and relieved *quickly*, in most cases *no special post-anesthesia care is required*. However, **postoperative oxygen desaturation** should be evaluated with **auscultation** of the chest and a CXR to rule out **negative pressure pulmonary edema (NPPE)**.

Answer 74

This complication occurs more commonly in older children and adults, who can develop more forceful inspiration against closed vocal cords, than in young children.

Answer 75

•Patients should be monitored in the PACU for **two or more hours afte**r an episode of severe laryngospasm. If NPPE occurs, a longer period of observation or overnight hospital **admission** may be required to allow time for resolution.

Answer 76

use of regional anesthetic and analgesic techniques has greatly increased. Commonly used include: * fentanyl (1–2 mcg/kg) * morphine (0.05–0.1 mg/kg) * hydromorphone (15 mcg/kg) \*don't need to know the doses

Answer 77

* A multimodal technique incorporating **ketorolac** (0.5–0.75 mg/kg) and intravenous **dexmedetomidine** will reduce opioid requirements. * Oral, rectal, or intravenous **acetaminophen** will also reduce opioid requirements and can be a helpful substitute for ketorolac

Answer 78

•Patient-controlled analgesia can also be successfully used in patients as young as **5 years old**, depending on their maturity and on preoperative preparation. * Commonly used opioids include morphine and hydromorphone.

Answer 79

Epidural infusions for postoperative analgesia often consist of a local anesthetic combined with an opioid. * Bupivacaine, 0.1% to 0.125%, or ropivacaine, 0.1% to 0.2%, are often combined with fentanyl, 2 to 2.5 mcg/mL (or equivalent concentrations of morphine or hydromorphone). * Recommended infusion rates depend on the size of the patient, the final drug concentration, and the location of the epidural catheter * Local anesthetic infusions can also be used with continuous nerve block techniques, but this is less common than in adults.

Answer 80

Correct tube size and appropriate cuff inflation is confirmed by easy passage into the larynx and the development of a gas leak at 15 to 25 cm H2O pressure.